Inter-Research > MEPS > v460 > p49-61  
Marine Ecology Progress Series

via Mailchimp

MEPS 460:49-61 (2012)  -  DOI:

Cascading effects of the ctenophore Mnemiopsis leidyi on the planktonic food web in a nutrient-limited estuarine system

J. Dinasquet1,2, J. Titelman3, L. F. Møller4, O. Setälä5, L. Granhag4, T. Andersen3, U. Båmstedt6, M. Haraldsson4, A. Hosia7, T. Katajisto5, T. Kragh8, J. Kuparinen5, M.-L. Schrøter1, M. Søndergaard8, P. Tiselius4, L. Riemann1,2,* 

1Department of Natural Sciences, Linnaeus University, Kalmar, 39182 Kalmar, Sweden
2Marine Biological Section, University of Copenhagen, 3000 Helsingør, Denmark
3Department of Biology, University of Oslo, 0316 Oslo, Norway
4Department of Biological and Environmental Sciences−Kristineberg, University of Gothenburg, 405 30 Gothenburg, Sweden
5Department of Environmental Sciences, University of Helsinki, 00014 Helsinki, Finland
6Department of Ecology and Environmental Sciences, Umeå University, 901 87 Umeå, Sweden
7Institute of Marine Research, 5817 Bergen, Norway
8Freshwater Biological Laboratory, University of Copenhagen, 3400 Hillerød, Denmark
*Corresponding author. Email:

ABSTRACT: Increasing biomasses of gelatinous zooplankton presumably have major implications for the structure and function of marine food webs at large; however, current data on lower trophic levels are scarce, as most studies have focused on the immediate effects on zooplankton and fish larvae only. We examined the short-term impact of larvae and adults of the invasive ctenophore Mnemiopsis leidyi on a summer planktonic food web in the estuarine southern Baltic Sea, with special emphasis on the microbial loop. Grazing by M. leidyi reduced the mesozooplankton biomass, followed by increased dinoflagellate biomass in treatments with M. leidyi. While chlorophyll a increased most in the treatments with M. leidyi, small phytoplankton and ciliates decreased in all treatments. M. leidyi had a slight effect on bacterial abundance, but not on bacterial production, ectoenzymatic activities, or community composition. Undetectable levels of phosphate and a gradual accumulation of dissolved organic carbon during the experiment suggested a malfunctioning microbial loop scenario. The experiment shows that direct and indirect short-term effects of M. leidyi on the estuarine food web are limited to higher trophic levels and indicates that top-down and bottom-up consequences of M. leidyi expansions on the microbial loop will likely depend on local nutrient conditions.

KEY WORDS: Bacterioplankton · Nanoflagellates · Microbial loop · Trophic levels · Ciliates · Baltic Sea

Full text in pdf format 
Cite this article as: Dinasquet J, Titelman J, Møller LF, Setälä O and others (2012) Cascading effects of the ctenophore Mnemiopsis leidyi on the planktonic food web in a nutrient-limited estuarine system. Mar Ecol Prog Ser 460:49-61.

Export citation
RSS - Facebook - - linkedIn